warning lights GMC SIERRA 2023 Owners Manual

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
56 Seats and Restraints
Obstructions
If something has blocked the seat while
recalling a memory position, the recall may
stop. Remove the obstruction and try the
recall again. If the memory position still
does not recall, see your dealer.
Heated and Ventilated Front
Seats
{Warning
If temperature change or pain to the skin
cannot be felt, the seat heater may cause
burns. To reduce the risk of burns, use
care when using the seat heater,
especially for long periods of time. Do
not place anything on the seat that
insulates against heat, such as a blanket,
cushion, cover, or similar item. This may
cause the seat heater to overheat. An
overheated seat heater may cause a burn
or may damage the seat.Heated and Ventilated Seat Buttons Shown,Heated Seat Buttons Similar
If equipped, the buttons are on the center
stack. To operate, the engine must be
running.
Press
Ior+to heat the driver or
passenger seatback only.
Press
Jorzto heat the driver or
passenger seat cushion and seatback.
Press
Cor{to ventilate the driver or
passenger seat.
The indicator light on the button comes on
when this feature is on. Press the button once for the highest
setting. With each press of the button, the
seat will change to the next lower setting,
and then to the off setting. The indicator
lights next to the buttons indicate three for
the highest setting and one for the lowest.
If the heated seats are on high, their level
may automatically be lowered after
approximately 30 minutes.
Remote Start Heated and Ventilated Seats
If equipped, the heated seats will turn on
automatically during a remote start if it is
cold outside and the ventilated seats will
turn on automatically if it is hot outside.
If equipped, the heated steering wheel will
turn on automatically during a remote start
if it is cold outside. The heated and
ventilated seat indicators and heated
steering wheel indicator may come on
during this operation.
The heated and ventilated seats and heated
steering wheel may cancel when the vehicle
is started. These features can be manually
selected after the vehicle is turned on.
The temperature performance of an
unoccupied seat may be reduced. This is
normal.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
58 Seats and Restraints
Heated Rear Seats
{Warning
If you cannot feel temperature change or
pain to the skin, the seat heater may
cause burns. See the Warning under
Heated and Ventilated Front Seats056.
If available, the buttons are on the rear of
the center console. To operate, the engine
must be running.
Press
MorLto heat the left or right
outboard seat cushion. An indicator on the
climate control display appears when this
feature is on. This feature turns on at the highest setting.
With each press of the button, the heated
seat changes to the next lower setting, and
then the off setting. Three lights indicate
the highest setting, and one light indicates
the lowest. If the heated seats are on high,
the level may automatically be lowered
after approximately 30 minutes.
Seat Belts
This section describes how to use seat belts
properly, and some things not to do.
{Warning
Do not let anyone ride where a seat belt
cannot be worn properly. In a crash,
if you or your passenger(s) are not
wearing seat belts, injuries can be much
worse than if you are wearing seat belts.
You can be seriously injured or killed by
hitting things inside the vehicle harder or
by being ejected from the vehicle. In
addition, anyone who is not buckled up
can strike other passengers in the vehicle.
It is extremely dangerous to ride in a
cargo area, inside or outside of a vehicle.
In a collision, passengers riding in these
(Continued)
Warning (Continued)
areas are more likely to be seriously
injured or killed. Do not allow passengers
to ride in any area of the vehicle that is
not equipped with seats and seat belts.
Always wear a seat belt, and check that
all passenger(s) are restrained
properly too.
This vehicle has indicators as a reminder to
buckle the seat belts. See Seat Belt
Reminders 0118.
Why Seat Belts Work

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
104 Instruments and Controls
Instruments and Controls
Controls
Steering Wheel Adjustment . . . . . . . . . . . 105
Heated Steering Wheel . . . . . . . . . . . . . . . . 105
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Windshield Wiper/Washer . . . . . . . . . . . . 106
Compass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Power Outlets . . . . . . . . . . . . . . . . . . . . . . . . . 107
Wireless Charging . . . . . . . . . . . . . . . . . . . . . 109
Warning Lights, Gauges, and Indicators
Warning Lights, Gauges, andIndicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Instrument Cluster . . . . . . . . . . . . . . . . . . . . . 111
Speedometer . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Odometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Trip Odometer . . . . . . . . . . . . . . . . . . . . . . . . . 115
Tachometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Fuel Gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Engine Oil Pressure Gauge . . . . . . . . . . . . . 116
Engine Coolant Temperature Gauge . . . . 117
Voltmeter Gauge . . . . . . . . . . . . . . . . . . . . . . 118
Seat Belt Reminders . . . . . . . . . . . . . . . . . . . 118
Airbag Readiness Light . . . . . . . . . . . . . . . . . 119
Passenger Airbag Status Indicator . . . . . . 119
Charging System Light . . . . . . . . . . . . . . . . 120
Malfunction Indicator Lamp (Check Engine Light) . . . . . . . . . . . . . . . . . . . . . . . . 120 Brake System Warning Light . . . . . . . . . . . 122
Electric Parking Brake Light . . . . . . . . . . . . 122
Service Electric Parking Brake Light . . . . 122
Antilock Brake System (ABS) Warning
Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
Four-Wheel-Drive Light . . . . . . . . . . . . . . . . . 123
Hill Descent Control Light . . . . . . . . . . . . . . 123
Lane Departure Warning (LDW) Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
Vehicle Ahead Indicator . . . . . . . . . . . . . . . . 124
Traction Off Light . . . . . . . . . . . . . . . . . . . . . . 124
Traction Control System (TCS)/Electronic Stability Control Light . . . . . . . . . . . . . . . . 124
Electronic Stability Control (ESC) Off Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Engine Coolant Temperature Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Driver Mode Control Light . . . . . . . . . . . . . 125
Tire Pressure Light . . . . . . . . . . . . . . . . . . . . . 126
Engine Oil Pressure Light (Uplevel Cluster) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
Low Fuel Warning Light . . . . . . . . . . . . . . . . 127
Security Light . . . . . . . . . . . . . . . . . . . . . . . . . . 127
High-Beam On Light . . . . . . . . . . . . . . . . . . . 127
Front Fog Lamp Light . . . . . . . . . . . . . . . . . . 128
Lamps On Reminder . . . . . . . . . . . . . . . . . . . 128
Cruise Control Light . . . . . . . . . . . . . . . . . . . . 128
Door Ajar Light . . . . . . . . . . . . . . . . . . . . . . . . 128
Information Displays
Driver Information Center (DIC) (Base Level) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Driver Information Center (DIC) (Midlevel and Uplevel) . . . . . . . . . . . . . . . 130
Head-Up Display (HUD) . . . . . . . . . . . . . . . . 132
Vehicle Messages
Vehicle Messages . . . . . . . . . . . . . . . . . . . . . . 135
Engine Power Messages . . . . . . . . . . . . . . . 135
Vehicle Speed Messages . . . . . . . . . . . . . . . 135
Universal Remote System
Universal Remote System . . . . . . . . . . . . . . 135
Universal Remote System
Programming . . . . . . . . . . . . . . . . . . . . . . . . 136
Universal Remote System Operation . . . 137

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Instruments and Controls 111
Warning Lights, Gauges, and
Indicators
Warning lights and gauges can signal that
something is wrong before it becomes
serious enough to cause an expensive repair
or replacement. Paying attention to the
warning lights and gauges could prevent
injury.
Some warning lights come on briefly when
the engine is started to indicate they are
working. When one of the warning lights
comes on and stays on while driving,
or when one of the gauges shows there
may be a problem, check the section that
explains what to do. Waiting to do repairs
can be costly and even dangerous.
Instrument Cluster
English Base Cluster Shown, Metric Similar
1.Tachometer 0115
2. Engine Oil Pressure Gauge 0116
3. Engine Coolant Temperature Gauge
0117
4. Fuel Gauge 0115
5. Voltmeter Gauge 0118 6.
Speedometer 0115
7. Driver Information Center (DIC) (Base
Level) 0128 or
Driver Information Center (DIC)
(Midlevel and Uplevel) 0130

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
120 Instruments and Controls
will light either ON or OFF, or either the on
or off symbol, to let you know the status of
the front outboard passenger frontal airbag.
If the word ON or the on symbol is lit on
the passenger airbag status indicator, it
means that the front outboard passenger
frontal airbag is allowed to inflate.
If the word OFF or the off symbol is lit on
the passenger airbag status indicator, it
means that the passenger sensing system
has turned off the front outboard passenger
frontal airbag.
If, after several seconds, both status
indicator lights remain on, or if there are no
lights at all, there may be a problem with
the lights or the passenger sensing system.
See your dealer for service.
{Warning
If the airbag readiness light ever comes
on and stays on, it means that
something may be wrong with the airbag
system. To help avoid injury to yourself
or others, have the vehicle serviced right
away. SeeAirbag Readiness Light 0119
for more information, including important
safety information.
Charging System Light
The charging system light comes on briefly
when the ignition is turned on, but the
engine is not running, as a check to show
the light is working. It should go out when
the engine is started.
If the light stays on, or comes on while
driving, there may be a problem with the
electrical charging system. Have it checked
by your dealer. Driving while this light is on
could drain the battery.
When this light comes on, or is flashing, the
Driver Information Center (DIC) also displays
a message.
If a short distance must be driven with the
light on, be sure to turn off all accessories,
such as the radio and air conditioner. Find a
safe place to stop the vehicle.
Malfunction Indicator Lamp
(Check Engine Light)
This light is part of the vehicle’s emission
control on-board diagnostic system. If this
light is on while the engine is running, a
malfunction has been detected and the
vehicle may require service. The light should
come on to show that it is working when
the ignition is on and the engine is not
running. See Ignition Positions (Key Access)
0 221 or
Ignition Positions (Keyless Access) 0223.
Malfunctions are often indicated by the
system before any problem is noticeable.
Being aware of the light and seeking service
promptly when it comes on may prevent
damage.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Lighting 139
Lighting
Exterior Lighting
Exterior Lamp Controls . . . . . . . . . . . . . . . . 139
Exterior Lamps Off Reminder . . . . . . . . . . . 141
Headlamp High/Low-Beam Changer . . . . 141
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Daytime Running Lamps (DRL) . . . . . . . . . 141
Automatic Headlamp System . . . . . . . . . . 141
Hazard Warning Flashers . . . . . . . . . . . . . . 142
Turn and Lane-Change Signals . . . . . . . . . 143
Fog Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Task Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . 144
Auxiliary Roof-Mounted Lamp . . . . . . . . . 144
Exterior Cargo Lamps . . . . . . . . . . . . . . . . . . 144
Interior Lighting
Instrument Panel IlluminationControl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
Dome Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . 145
Reading Lamps . . . . . . . . . . . . . . . . . . . . . . . . 146
Lighting Features
Entry Lighting . . . . . . . . . . . . . . . . . . . . . . . . . 146
Exit Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Battery Load Management . . . . . . . . . . . . 147
Battery Power Protection . . . . . . . . . . . . . . 147
Exterior Lighting Battery Saver . . . . . . . . 147
Exterior Lighting
Exterior Lamp Controls
The exterior lamp control is on the
instrument panel to the left of the steering
wheel.
O: Turns off the automatic headlamps and
Daytime Running Lamps (DRL). Turn the
headlamp control to
Oagain to turn the
automatic headlamps or DRL back on.
For vehicles first sold in Canada, off will only
work when the vehicle is in P (Park). AUTO :
Automatically turns on the
headlamps, parking lamps, taillamps,
instrument panel lights, roof marker lamps
(if equipped), front/rear sidemarker lamps,
and license plate lamps.
;: Turns on the parking lamps including
all lamps, except the headlamps and fog
lamps, if equipped.
For some trim levels and series of trucks
first sold in Canada, the headlamps may
turn on with the parking lamps.
2: Turns on the headlamps together with
the parking lamps, taillamps, instrument
panel lights, roof marker lamps (if
equipped), front/rear sidemarker lamps, and
license plate lamps.
When the headlamps are turned on while
the vehicle is on, the headlamps turn off
automatically 10 minutes after the ignition
is turned off. When the headlamps are
turned on while the vehicle is off, the
headlamps will stay on for 10 minutes
before turning off to prevent the battery
from being drained. Turn the headlamp
control off and then back to the headlamp
on position to make the headlamps stay on

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
142 Lighting
There is a light sensor on top of the
instrument panel. Do not cover the sensor,
otherwise the headlamps will come on when
they are not needed.
The system may also turn on the headlamps
when driving through a parking garage or
tunnel.
If the vehicle is started in a dark garage, the
automatic headlamp system comes on
immediately. If it is light outside when the
vehicle leaves the garage, there is a slight
delay before the automatic headlamp
system changes to the Daytime Running
Lamps (DRL). During that delay, the
instrument cluster may not be as bright as
usual. Make sure the instrument panelillumination control is in the full bright
position. See
Instrument Panel Illumination
Control 0145.
When it is bright enough outside, the
headlamps will turn off or may change
to DRL.
The automatic headlamp system turns off
when the exterior lamp control is turned to
Oor the ignition is off.
Lights On with Wipers
If the windshield wipers are activated in
daylight with the engine on, and the
exterior lamp control is in AUTO, the
headlamps, parking lamps, and other
exterior lamps come on. The transition time
for the lamps coming on varies based on
wiper speed. When the wipers are not
operating, these lamps turn off. Move the
exterior lamp control to
Oor;to disable
this feature.
Hazard Warning Flashers
|: Press this button to make the front
and rear turn signal lamps flash on and off.
Press again to turn the flashers off.
When the hazard warning flashers are on,
the vehicle's turn signals will not work.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Driving and Operating 223
Caution
Use the correct key, make sure it is all
the way in—or pushed all the way in
toward the steering column when turning
off the vehicle —and turn it only with
your hand.
1 (ACC/ACCESSORY) : This position allows
features such as the infotainment system to
operate while the vehicle is off. It also
unlocks the steering column, if equipped
with a locking steering column. Use this
position if the vehicle must be pushed or
towed. See Retained Accessory Power (RAP)
0 227.
From ON/RUN, push the key all the way in
toward the steering column, then turn the
key to ACC/ACCESSORY.
If the key is left in ACC/ACCESSORY with the
engine off, the battery could drain and the
vehicle may not start.
A warning chime will sound when the driver
door is opened and the key is in the
ignition.
2 (ON/RUN) : This position can be used to
operate the electrical accessories and to
display some instrument cluster warning
and indicator lights. This position can also be used for service and diagnostics, and to
verify the proper operation of the
malfunction indicator lamp as may be
required for emission inspection purposes.
The switch stays in this position when the
engine is running. The transmission is also
unlocked in this position.
If the key is left in ON/RUN with the engine
off, the battery could drain and the vehicle
may not start.
3 (START) :
This is the position that starts
the engine. When the engine starts, release
the key. The ignition returns to ON/RUN for
driving.
Ignition Positions (Keyless Access)
Vehicles equipped with Keyless Access have
pushbutton starting.
The remote key must be in the vehicle for
the system to operate. If the pushbutton
start is not working, the vehicle may be
near a strong radio antenna signal causing
interference to the Keyless Access system.
See Remote Keyless Entry (RKE) System
Operation (Key Access) 012 or
Remote Keyless Entry (RKE) System
Operation (Keyless Access) 014.
To shift out of P (Park), the ignition must be
on or in Service Mode, and the brake pedal
must be applied.
{Warning
Turning off the vehicle while moving may
cause loss of power assist in the brake
and steering systems and disable the
airbags. While driving, only shut the
vehicle off in an emergency.
Stopping the Engine/LOCK/OFF (No Indicator
Lights) : When the vehicle is stopped, press
ENGINE START/STOP once to turn the
engine off.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Driving and Operating 257
vehicle personalization. The On with Towbar
setting allows Park Assist to work properly
with a trailer hitch. Some larger trailer
hitches may not be compatible.
To view available settings for this feature,
touch the Settings icon on the infotainment
home page. Select“Vehicle”to display the
list of available options and select “Collision/
Detection Systems”.
Turn off Park Assist when towing a trailer.
To turn the “Rear Camera Park Assist
Symbols” on or off, touch the Settings icon
on the infotainment home page. Select
“Vehicle” to display the list of available
options and select “Collision/Detection
Systems”.
Rear Cross Traffic Alert (RCTA)
System
If equipped, Rear Cross Traffic Alert (RCTA)
displays a red warning triangle with a left
or right pointing arrow on the infotainment
display to warn of traffic coming from the
left or right. This system detects objects
coming from up to 20 m (65 ft) from the left
or right side of the vehicle. When an object
is detected, either three beeps sound from
the left or right or three Safety Alert Seat pulses occur on the left or right side,
depending on the direction of the detected
vehicle.
Driving With a Trailer
Use caution while backing up when towing
a trailer. The RCTA feature is automatically
disabled when a trailer is attached to the
vehicle.
Turning the Features On or Off
The
Xbutton on the center stack is used
to turn on or off the Rear Park Assist (RPA),
and Backing Warning and Reverse Automatic
Braking (RAB) systems at the same time.
The indicator light next to the button comes
on when the features are on and turns off
when the features have been disabled.
Turn off RPA, RCTA, and RAB when towing a
trailer.
RCTA can be turned on or off using the
infotainment system. To view available
settings from the infotainment screen, touch
Settings > Vehicle > Collision/Detection
Systems.
Assistance Systems for Driving
If equipped, when driving the vehicle in a
forward gear, Forward Collision Alert (FCA),
Lane Keep Assist (LKA), Lane Departure
Warning (LDW), Side Blind Zone Alert (SBZA),
Lane Change Alert (LCA), and/or the
Automatic Emergency Braking (AEB) can help
to avoid a crash or reduce crash damage.
Forward Collision Alert (FCA)
System
If equipped, the FCA system may help to
avoid or reduce the harm caused by
front-end crashes. When approaching a
vehicle ahead too quickly, FCA provides a
red flashing alert on the windshield and
rapidly beeps or pulses the driver seat. FCA
also lights an amber visual alert if following
another vehicle much too closely.
FCA detects vehicles within a distance of
approximately 60 m (197 ft) and operates at
speeds above 8 km/h (5 mph).

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Driving and Operating 261
part of the Lane Change Alert (LCA) system,
read the entire LCA section before using this
feature.
Lane Change Alert (LCA)
If equipped, the LCA system is a
lane-changing aid that assists drivers with
avoiding lane change crashes that occur with
moving vehicles in the side blind zone (or
spot) areas or with vehicles rapidly
approaching these areas from behind. The
LCA warning display will light up in the
corresponding outside side mirror and will
flash if the turn signal is on.
{Warning
LCA does not alert the driver to vehicles
outside of the system detection zones,
pedestrians, bicyclists, or animals. It may
not provide alerts when changing lanes
under all driving conditions. Failure to use
proper care when changing lanes may
result in injury, death, or vehicle damage.
Before making a lane change, always
check mirrors, glance over your shoulder,
and use the turn signals.LCA Detection Zones
1. SBZA Detection Zone
2. LCA Detection Zone
The LCA sensor covers a zone of
approximately one lane over from both
sides of the vehicle, or 3.5 m (11 ft). The
height of the zone is approximately between
0.5 m (1.5 ft) and 2 m (6 ft) off the ground.
The Side Blind Zone Alert (SBZA) warning
area starts at approximately the middle of
the vehicle and goes back 5 m (16 ft). Drivers
are also warned of vehicles rapidly
approaching from up to 70 m (230 ft) behind
the vehicle.
How the System Works
The LCA symbol lights up in the side mirrors
when the system detects a moving vehicle
in the next lane over that is in the side blind zone or rapidly approaching that zone
from behind. A lit LCA symbol indicates it
may be unsafe to change lanes. Before
making a lane change, check the LCA
display, check mirrors, glance over your
shoulder, and use the turn signals.
Left Side Mirror
DisplayRight Side Mirror Display
When the vehicle is started, both outside
mirror LCA displays will briefly come on to
indicate the system is operating. When the
vehicle is in a forward gear, the left or right
side mirror display will light up if a moving
vehicle is detected in the next lane over in
that blind zone or rapidly approaching that
zone. If the turn signal is activated in the
same direction as a detected vehicle, this
display will flash as an extra warning not to
change lanes.
LCA can be disabled through vehicle settings.
When you disable LCA, SBZA is also disabled.
To view available settings from the